Help me, Dr. Internet!
I can't really get a straight answer on this, and am hoping someone out there has a good solution.
Every year, I make a huge several-terrabyte backup of my entire system. When I was on Windows, I used RAR for this. Good compression, was able to break it up in 4GB file blocks to make file access easy if I needed something off the backup or repair an archive.
I've long since moved to TAR.XZ for intermediate backups, but the access takes forever cause it's a single archive, so I've never used it for my large once-a-year-complete-backup.
That said, the question: would it be worth doing the Full Everything Backup with tar.xg over jumping into Windows to WinRAR it (Day 9023849283468923 of my 30 day trial!)? In general does RAR pack tighter than TAR.XZ? Can TAR.XZ break itself into chunks for easier access?
My update is scheduled for January 1st. Any help would be appreciated! And thanks in advance!
@dolari It's a little bit old and doesn't have .xz in the results but
https://ubuntuguru.wordpress.com/2007/03/09/whats-the-best-file-compression-method/
indicates you might get a little bit better compression if you use 7zip? You'd have some similar tradeoffs to rar in that it supports random access to the archived data but does not store UNIX permissions.
@MorningSong - For a while I used 7Zip, but I stopped about a decade ago when an archive broke and there were zero recovery options for it. I looked into it again after someone told me that 7Zip was better compression, and thier recovery irons were a bit...arcane.
@MorningSong - I've found a good set of strings for RAR archiving that worked for me. I actually installed WinRAR on a Windows partition, clicked all the buttons and clicks I use for my yearly updates, and found the corresponding strings. I think I managed it!
Incremental Monthly Home Directory Backup
rar a -m5 -r -s -v5370000 -x/home/dolari/.local/share/Trash/ -ep2 -ol -rr -taYYYYMMDDHHSS -tbYYYYMMDDHHSS "YYMM Incremental Nayru Home Directory Backup.rar" /home/dolari/
Incremental Monthly Backup:
rar a -m5 -r -s -v5370000 -x"/mnt/The Archive/Videos/" -x"/mnt/The Archive/00_DUMP/Videos/" -x"/mnt/The Archive/.Trash-1000/" -x"/mnt/The Archive/Working Directory/" -ep2 -ol -rr -taYYYYMMDDHHSS -tbYYYYMMDDHHSS "YYMM Incremental Backup.rar" "/mnt/The Archive"
Full Home Directory Backup
rar a -m5 -r -s -v5370000 -x/home/dolari/.local/share/Trash/ -ep2 -ol -rr "YYMM Nayru Home Directory Backup.rar" /home/dolari/
Full Yearly Backup
rar a -m5 -r -s -v5370000 -x"/mnt/The Archive/Videos/" -x"/mnt/The Archive/00_DU
@dolari nice!
I should probably automate my backups at some point.
@dolari Fair!
I don't know how RAR recovery is, but it *is* worth noting that this author has another strike against .xz along those lines, specifircally citing its error recovery being unreliable.
https://www.nongnu.org/lzip/xz_inadequate.html